They can lose air due to stretching, but it should not be a very noticeable amount overnight. Take a spray bottle filled with soapy water. Spray the mattress and wherever it starts to bubble, there is a leak. ... View related article.
If they are on the ceiling, maybe a small paper lantern light fixutre you can get from a dollar store or walmart to cover them or a cute baby hat might work too. If they are on the walls, baby hats, wall art, a tapestry. Hope this helps. ... View related article.
You do the same thing you would to find a leak in a tire; a spray bottle filled with soapy water. Spray the soapy water on the air mattress while it is inflated. Wherever bubbles start to develop is where your leak is. ... View related article.
